Silver halide photographic materials having been exposed to light are generally processed by the steps of development, fixing, and washing or stabilization. When development processing is performed using an automatic developing machine, a replenisher for a developer and a replenisher for a fixer are generally prepared by dissolving the appropriate components constituting each processing solution in water followed by mixing, and the thus-prepared replenisher is reserved in a replenisher tank and fed in a given amount to a developing tank or a fixing tank of the automatic developing machine.
The above-described automatic processing system, including automatic replenishment, is a system established through use for years. However, with the recent development of electronic equipment, the basic system in which silver halide photographic materials are wet processed has been proved to have some disadvantages.
Specifically, the components for each of the developer and fixer are dissolved in water and mixed to prepare a processing solution, and stock tanks for the thus prepared processing solutions must be provided. Further, although chemical mixers are now widely used, the disadvantage remains that the processing solutions are essentially prepared from several components and extra space is required for a chemical mixer in addition to the space for the automatic developing machine.
In order to make rapid processing possible, an emulsion-hardening reaction is generally performed during processing. However, glutaraldehyde which is usually incorporated in a developer as a hardening agent gives off an irritating smell and also is hazardous in contact with the skin. When hardening is effected by an aluminum salt which is generally used in a fixer, it is necessary to adjust the pH of the fixer to a range of from 4.2 to 4.6, at which the highest hardening reactivity can be attained, in order to suppress swelling with washing water and thereby to lessen the drying load. In this pH range, however, a part of the thiosulfate used as a main component of the fixer decomposes to generate sulfurous acid gas. Also, acetic acid, which is used as a pH buffering agent, produces a gas, thus resulting in contamination of the working environment with unpleasant smells. In some extreme cases, the produced sulfurous acid gas corrodes not only the automatic developing machine but also surrounding equipment through long-term use.
One of the causes of the above-described problems associated with automatic development lies in the hardening reaction during processing, which is usually performed by glutaraldehyde in a developer or an aluminum salt in a fixer. It has previously been known that many of the above problems can be solved by entirely omitting the glutaraldehyde hardening reaction, or by conducting the aluminum salt hardening reaction, if used, at a pH of 4.65 or higher to reduce its hardening reactivity.
In such a development processing system without a hardening step, it is essential that silver halide photographic materials should be sufficiently hardened in advance. However, if silver halide photographic materials having high sensitivity and high density, such as X-ray films for medical use, are sufficiently hardened beforehand, the required amount of silver coated must be increased, which is unfavorable from the standpoint of conservation of resources and cost.
Recently orthochromatic films used in combination with a screen containing a rare earth element have been adopted in medical X-ray photography because of improved image quality. In the orthochromatic films, the image quality can further be improved by using tabular silver halide grains so that high density may be obtained with a decreased silver coverage. Such orthochromatic films have already been marketed.
The above-described light-sensitive materials containing tabular silver halides do not undergo serious reduction in density, even when pre-hardened; that is, they exhibit sufficient photographic properties without hardening during processing, as disclosed in Research Disclosure, No. 22534 (Jan., 1983) and Japanese Patent Application (OPI) No. 111933/83 (the term "OPI" as used herein refers to a "published unexamined Japanese patent application").
Even if hardening during processing may be omitted by means of the above-mentioned techniques, automatic development still involves complicated preparation of processing solutions because the processing solutions consists of many components (i.e., plural parts). The complexity of the solutions has prevented simplification of processing solution preparation and size reduction of automatic developing machines.
Moreover, more rapid processing has been keenly demanded in the art. In particular, the total development time (i.e., from dry to dry) required for automatic processing of X-ray films by the use of conventional developing machines generally ranges from 90 seconds to 3 and a half minutes, and a further reduction of processing time is desired.